RadioShack MPA-50 - Manuals

Page 2 - Contents

2 ˆ Contents Features ................................................................................................................... 3 Preparation .............................................................................................................. 4 Presetting the Controls ..............

Page 3 - Features

3 Features ˆ Features Your RadioShack MPA-50 40-Watt PAAmplifier gives you 40 watts of solidpower for your public address (PA) sys-tem. The built-in three-band equalizerenables you to tailor the sound to fit yourenvironment. Its wide frequency re-sponse easily handles amplification ofvoice and music...

Page 4 - Preparation; CHOOSING A LOCATION

4 Preparation ˆ Preparation PRESETTING THE CONTROLS Warning: A sudden high output from theamplifier could damage your hearing orthe speakers connected to the amplifi-er’s output. To avoid accidentally overdriving achannel or prematurely amplifying anaudio input, set all the amplifier’s front-panel c...

Page 5 - Making Connections

5 Making Connections ˆ Making Connections Important: Connect all auxiliary equipment and speakers before connecting power. PHONO L (Left) and R (Right) InputJacks — Connect a turntable with amagnetic cartridge. To avoid distortion,do not connect a high-level audio inputsource to these jacks. Even th...

Page 6 - Speakers; SPEAKER PHASING

6 Speakers ˆ Speakers SPEAKER PHASING Phasing is the direction the speakercone moves with reference to the polari-ty of the connection wires. Proper phas-ing is important when you use more thanone speaker in the same room or area.Out-of-phase speakers can lose up toone-half of their potential volume...

Page 7 - CONNECTING SPEAKERS

7 Speakers determine if your speakers are connect-ed in series, parallel, or series/parallelcombined. Note: We recommend that you usespeakers that are rated the same (forexample, all 8-ohm speakers) for all se-ries or parallel connections. • Speakers are connected in series when the first speaker’s ...

Page 8 - One Speaker

8 Speakers One Speaker Connect the speaker’s negative (–) ter-minal to the amplifier’s COM (common) terminal. Then connect the speaker’spositive (+) terminal to the amplifier’sterminal that matches the speaker’s im-pedance. For example, if you have an 8-ohm speaker, connect the speaker’spositive ter...

Page 12 - Controls and Operation

12 Controls and Operation ˆ Controls and Operation MICROPHONE 1 and 2 Inputs — Con-nect any standard dynamic microphonewith a 1 / 4 -inch plug. POWER Switch and Indicator — Pressthe bottom half of the switch to turn onthe amplifier. The indicator lights. Pressthe top half of the switch to turn off t...

Page 13 - Troubleshooting

13 Troubleshooting ˆ Troubleshooting If you should run into difficulties, checkthe wiring of the system. Are there anyshort circuits in the speaker wiring?Have you provided adequate ventila-tion? Did you calculate speaker imped-ance correctly? Be sure microphones and connectingcables are not defecti...

Page 14 - Care; REPLACING THE FUSE

14 Care ˆ Care To enjoy your MPA-50 40-Watt PA Am-plifier for a long time: • Keep the amplifier dry. If it gets wet, wipe it dry immediately. • Use and store the amplifier only in normal temperature environments. • Handle the amplifier gently and carefully. Don’t drop it. • Keep the amplifier away f...

Page 15 - Specifications

15 Specifications ˆ Specifications Output Power at 1 kHz, 10% THD ............................................................................... 40 Watts Power Bandwidth at 1W, 10% THD, Auxiliary Input ............................................ 70 Hz–20 kHz THD at 2W, 1 kHz MIC1 ....................